Comment 0 for bug 1765897

-- BACKGROUND info -- (ie. skip!)
I upgraded to 18.04 last night from 17.10 (Ubuntu with GNOME, but also XFCE & MATE DEsktops were installed). I logged in last night & noticed nothing unusual (slow login, crash & apport bug report made [duplicate]). Otherwise upgrade was perfect. Last night I only used MATE.
-- END background

Today I logged into GNOME (first login since upgrade), my screen config was changed (as if side-by-side) so I altered to match my config - and now on top (secondary) screen left side of screen I get this few pixel wide graphic 'bar' type glitch.

It alters with screen-draws; having minimal movement is nothing on screen is drawing. If you move mouse it jumps more, if you move windows the movement is even more - when I start music (audacious) which has a graphic audio metre (dancing with music) I get lots of activity on the glitch-bar.

If I move audacious below (top) screen it still acts as if on screen (my screen placement i think is reason for this), but if I minimize the window the glitch has minimal movement, likewise if I move audacious to lower (primary) screen and move the bar off display.

As stated, the vertical-graphic-lines-glitch appears to be related to movement or redrawing of stuff on screen. If I stop music and have ~everything static but type into the `hexchat` screen on the bottom, the vertical-graphic-lines-glitch jumps on each keypress (or its being written to screen). If i hit random keys quickly the jumping movement is faster than slow keypresses

If I make no movements, glitch still has movement; maybe 2-4 moves per second., but a fraction of the 'jumps' (or movement) of when there is graphic movement.

OF NOTE: As I type this into chromium, the 'glitch' is the smallest its been and NOT moving to each keystroke which is different behavior to terms, hexchat etc.

This behavior is only evident in GNOME.

guiverc@d960-ubu2:~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu Bionic Beaver (development branch)
Release: 18.04
Codename: bionic

guiverc@d960-ubu2:~$ sudo lshw -C video
  *-display
       description: VGA compatible controller
       product: Cedar [Radeon HD 5000/6000/7350/8350 Series]
       vendor: Advanced Micro Devices, Inc. [AMD/ATI]
       physical id: 0
       bus info: pci@0000:01:00.0
       version: 00
       width: 64 bits
       clock: 33MHz
       capabilities: pm pciexpress msi vga_controller bus_master cap_list rom
       configuration: driver=radeon latency=0
       resources: irq:30 memory:e0000000-efffffff memory:f7de0000-f7dfffff ioport:dc00(size=256) memory:c0000-dffff

guiverc@d960-ubu2:~$ sudo apt-cache policy gnome-session
gnome-session:
  Installed: (none)
  Candidate: 3.28.1-0ubuntu2
  Version table:
     3.28.1-0ubuntu2 500
        500 http://ftp.iinet.net.au/pub/ubuntu bionic/universe amd64 Packages
        500 http://au.archive.ubuntu.com/ubuntu bionic/universe amd64 Packages

For a bad video of what I see/mean - see https://www.youtube.com/watch?v=e5KA1as_lVA

(if it wasn't mostly white & bright-blue bars - it'd be less annoying)

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: gnome (not installed)
ProcVersionSignature: Ubuntu 4.15.0-15.16-generic 4.15.15
Uname: Linux 4.15.0-15-generic x86_64
ApportVersion: 2.20.9-0ubuntu5
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Sat Apr 21 13:59:30 2018
EcryptfsInUse: Yes
InstallationDate: Installed on 2017-11-16 (156 days ago)
InstallationMedia: Ubuntu 17.10 "Artful Aardvark" - Release amd64 (20171018)
SourcePackage: meta-gnome3
UpgradeStatus: No upgrade log present (probably fresh install)